Process for obtaining epsilon-substituted derivatives of caproic acid and its homologues, and the products thereof



United States Patent M 3,026,334 PROCESS FOR OBTAINING EPSILON-SUBSTI-TUTED DERIVATIVES OF CAPROIC ACID AND ITS HOMOLOGUES, AND THE PROD- UCTSTHEREOF Francesco Minisci, Milan, Italy, assignor to Montecatini SocietaGeneral per llndustria Mineraria e Chirnica, Milan, Italy, a corporationof Italy No Drawing. Filed Jan. 23, 1959, Ser. No. 788,491 Claimspriority, application Italy Jan. 28, 1958 16 Claims. (Cl. 260349) Thisapplication is in part a continuation of my copending application SerialNo. 734,448, filed May 12, 1958, and subsequently abandoned. Thatapplication describes the preparation of a number of epsilon-substitutedderivatives of caproic acid from cyclohexanone peroxide, more preciselythe chlorobromo-, iodo and cyanoderivatives.

It has now been found that other substances react with peroxides ofalicylic ketones such as cyclohexanone peroxide to give new derivatives.For example, by reaction with sodium azide, epsilon-azido-caproic, andby reaction with sulfur dioxide, epsilon-sulfonate-caproic acid areobtained.

Moreover, it has been found that these reactions have a more generalcharacter, and are valid for other peroxides obtained by action ofhydrogen peroxide on ketones or, in any case, having the structure ofoxy-peroxides, namely:

in which R and R are the same or different substituents, and represent Hor an alkyl or cycloalkyl group.

The present invention relates to the preparation of chloro-, bromo-,iodo-, cyano-, sulfocyano-, dithio-, azido-derivatives and sulfonicacids from a peroxide having the afore-mentioned structure and ahydrohalogenic substance or an alkaline halide, cyanide, sulfocyanide,thiosulfate, azide or sulfur dioxide, for example according to thefollowing scheme:

0\ MeX R1-oo0R R -X R2 OR in which R and R have the afore-mentionedmeaning; X is Cl, Br, I, CN, SCN, S-SR N SO H; and Me is an alkali oralkaline earth metal, including ammonium, for example, or is hydrogenpreferably where X is halogen.

Where a cyclic peroxide is used, only one product is obtained while, inthe case of acyclic derivatives, splitting into two products takesplace, one of which is always a carboxylic acid, in accordance with thefollowing scheme, in which R R and X have the afore-mentioned meaning.

The preferred process according to this invention consists in reactingthe peroxide at a temperature of between -20 and +50 C., preferably atbetween and +10 C., with one of the afore-mentioned reactants, in thepresence of substances capable of causing the decom- 3,026,334 PatentedMar. 20, 1962 position of the peroxide into radicals. Typical reducingsubstances of the kind used in redox systems are used, particularlysalts of heavy metals having variable valence, but employed in the formof the lower valence, for example, Cn+ and Fe++.

The reaction can be carried out in a single stage, using a suitablesolvent for the peroxide. It is, however, preferable to operate inaqueous solution, to improve the yield and to facilitate isolation ofthe reaction products. In the preparation of halogen derivatives eitherhydrohalic acids or alkaline halides can be used. The use of the latterdoes not offer any particular advantage, since at the end of thereaction the solution must be acidified in order to free the reactionproducts.

The reaction course can be schematized as follows:

This completely new synthesis makes it possible to obtain, by a rathersimple method, products which can hardly be prepared by other methods,and some of which products have not been known till now.

The following examples are illustrative and are not intended to limitthe scope of the present invention.

EXAMPLE 1 40 g. cyclopentanone peroxide are added under nitrogen to asolution containing 22 g. cuprous chloride and 24 g. hydrochloric acidin cc. water while stirring. The temperature is kept at 0 to 50 C., andthe reaction is completed within half an hour. After decantation of thereaction products, the acid portion, consisting of deltachloro-valericacid (19 g.) is separated from the neutral portion, consistingessentially of cyclopentanone (18 g.).

EXAMPLE 2 The preceding example is duplicated, using however 50 g.ferrous sulfate in place of cuprous chloride. Starting with the sameamount of peroxide, 17 g. delta-chlorovaleric acid and 22 g.cyclopentanone are obtained.

EXAMPLE 3 11 g. 4-methylcyclohexanone peroxide are added under nitrogento a solution containing 7 g. cuprous chloride and 5 g. hydrochloricacid in 50 cc. water at 510 C., within half an hour while stirring.

After decantation of the organic layer, 3.7 g, of a neutral portion,consisting essentially of 4-methylcyclohexanone and 6 g. of4-methyl-6-chloro-caproic acid, are separated by treatment withalkalies. The latter acid, not known till now, is a colorless liquidwhich boils at 1278 C. under 2 mm.

EXAMPLE 4 The preceding example is duplicated, however, ferrous sulfateis used instead of cuprous chloride and the temperature is kept between20 and 30 C. 4.5 g. 4-methylcyclohexanone and 4 g. of4-methyl-6-chloro-caproic acid, are obtained.

EXAMPLE 5 20 g. 2-methylcyclohexanone peroxide are added while stirringunder nitrogen to a solution containing 10 g. cuprous chloride and 10 g.hydrochloric acid in 60 cc. water 20-30 minutes, at a temperature of -5to 0 C.

After decantation of the oily layer, the components of the neutralportion, which essentially consists of 2- methylcyclohexanone (8 g.) and6-chloroenanthic acid (11 g.), are separated by treatment with alkalies.6- chloroenanthic acid, i.e. epsilon-chloro-enanthic acid, was not knownin the literature until now. It is a colorless liquid which boils at 99C. under 0.3 mm.

Upon operating under the same conditions but with ferrous sulfateinstead of cuprous chloride, practically identical results are obtained.

EXAMPLE 6 15 g. cyclopentanone peroxide are added while stirring to asolution containing 18 g. hydrobromic acid and 10 g. cuprous chloride in50 cc. water, within 30 minutes, at a temperature of 5 to C. Thereaction products are decanted from the aqueous solution and treatedwith an alkali. The neutral insoluble portion (4.7 g.) is thusseparated.

From the alkaline solution after cooling and acidificationdelta-bromo-valeric acid in the solid state is separated, of which 9 g.(M.P. 38-39 C.) are obtained.

By operating under the same conditions with ferrous sulfate instead ofcuprous chloride, 7.2 g. delta-bromovaleric acid are obtained, from thesame amount of peroxide.

EXAMPLE 7 33 g. Z-methylcyclohexanone peroxide are added to a solutionof 15 g. cuprous chloride and 50 g. hydrobromic acid in 100 cc. water,while stirring under nitrogen within 30 minutes, at S C. Afterdecantation of the reaction products, the 2-methylcyclohexanone isseparated from the acid fraction by treatment with alkalies. 20 g.6-bromoenanthic acid (i.e. epsilon-bromo-enanthic acid) are obtained. Itis a colorless liquid, not known until now, which boils at 114 C. under0.35 mm. pressure.

When using ferrous sulfate as decomposition agent slightly lower yieldsare obtained.

EXAMPLE 8 15 g. cyclopentanone peroxide are added, while stirring, to asolution containing 10 g. cuprous chloride and 20 g. potassium iodide in50 cc. water at a temperature of 050 C. Within 40 minutes. Sulfurdioxide is then bubbled through the solution in order to decolorizesame. The decolorized solution is then extracted with chloroform, andthe chloroform solution is treated with an aqueous sodium bicarbonatesolution. From the aqueous solution g. delta-iodo-valeric acid having amelting point of 55 C. are precipitated by acidification.

EXAMPLE 9 20 g. Z-methylcyclohexanone peroxide are added to a solutioncontaining 10 g. potassium cyanide and 8 g. cuprous cyanide in 30 cc.water. The operation is carried out while stirring at a temperaturebetween 5 and 10 C. within 1 hour. The solution is then filtered,slightly acidified and extracted with ether. The ether is thenevaporated and the residue is distilled under reduced pressure; at 138C. and under 0.8 mm. 0.6 g. epsilon-cyano-enanthic acid are distilled.

EXAMPLE 10 '17 g. l-oxy-l'-hydroperoxy-cyclohexyl-peroxide are added to12 g. cuprous cyanide, 9 g. potassium cyanide and 100 cc. water whilestirring. Temperature 5 to 10 C. When the reaction is completed theundissolved copper salt is filtered off, the oily portion consistingessentially of cyclohexanone (6.2 g.) is separated, acidified andextracted repeatedly with ether. After evaporation of ether, 7.6 g.epsilon-cyano-caproic acid are obtained. Compare Example 25, for a fieldof utility.

4 EXAMPLE 11 15 g. cyclopentanone peroxide are added to a solution of 7g. cuprous sulfocyanide and 14 g. ammonium sulfocyanide in 50 cc. water.Since a vigorous exothermic reaction takes place, the reaction liquidmust be highly cooled in order to keep the temperature at between 0 "and5 C. The unreacted cuprous sulfocyanide (6.2 g.) is filtered olf and thesolution is slightly acidified and ex--v tracted with chloroform. Thechloroform solution is treated with aqueous sodium bicarbonate. From theresulting aqueous solution 7.2 g. epsilon-sulfocyanovaleric acid areseparated by acidification. It is a colorless liquid, boiling at 155 C.under 1 mm., and was not known until now.

EXAMPLE 12 20 g. 2-methylcyclohexanone peroxide are added to a solutionof 7 g. cuprous sulfocyanide and 16 g. ammonium sulfocyanide in 50 cc.water while stirring, at S C. The mixture is slightly acidified andextracted with chloroform. The chloroform extract is treated with anaqueous sodium bicarbonate solution. By acidifying the latter solution,epsilon-sulfocyanenanthic acid is separated as viscous liquid. This acidwas not known until now. It is decomposed by distillation.

EXAMPLE 13 15 g. cyclohexanone are treated with 5.5 g. hydrogen peroxidein ether. The resulting solution is concentrated to a small volume andafter standing for 12 hours is added to a suspension of 10 g. CuSCN in asolution containing 17 g. NH SCN in 100 cc. water while stirring undernitrogen. The temperature is kept at between 0 and 5 C.

When the reaction is completed, the unreacted cuprous sulfocyanide isfiltered off, and the filtrate is acidified and the oily layer thusseparated is decanted. By means of bicarbonate solution, cyclohexanone(4.3 g.) is separated from epsilon-sulfocyan-caproic acid (16.2 g.). Thelatter, not known until now, is a liquid boiling at 160 C. under 0.7 mm.

added, While stirring, to a suspension of 22 g. CuSCN in a solutioncontaining 21.6 g. NH SCN in 125 cc. water. The temperature is kept at5-10 C. By operating as in the preceding example 13.7 g.epsilon-sulfocyan-caproic acid and 7.2 g. cyclohexanone are obtained.

EXAMPLE 15 The preceding example is duplicated with the exception that4.6 g. CuSCN instead of 22 g. are employed. At the end of the reaction 4g. CuSCN are recovered, and the same results are obtained as in thepreceding run.

EXAMPLE 16 EXAMPLE 17 30 g. cyclohexanone peroxide are added within 40minutes while stirring to a solution containing 14 g. sodium azide and40 g. ferrous sulfate heptahydrate in cc. water. Temperature 0 to 5 C.

When the reaction is completed the mixture is acidified still at a lowtemperature until the ferric salt precipitate is completely dissolved.The solution is extracted with ether and the ether extract is treatedwith a bicarbonate solution; by acidifying the latter,epsilon-azido-caproic acid is obtained. It is a colorless liquid, notknown until now, which is decomposed by heating or prolonged treatmentwith acids or alkalies.

By catalytic hydrogenation it yields epsilon-aminocaproic acid.

EXAMPLE 18 30 g. cyclohexanone peroxide are aded, while stirringcontinuously, to a suspension of 15 g. cuprous oxide, freshly prepared,in a solution of 14 g. sodium azide in 100 cc. water. The temperaturewas 10-15 C. The reaction proceeds more slowly than in the precedingexample and about 2 hours are necessary for completing same. When thereaction is ended, the reaction mixture is acidified while cooling, theinsoluble mineral residue is filtered off and the filtrate is extractedwith ether. By proceeding as in the preceding example 12 g.epsilonazido-caproic acid are obtained.

EXAMPLE 19 33 g. cyclopentanone peroxide are added within 30 minuteswhile stirring to a solution containing 14 g. sodium azide and 40 g.ferrous sulfate heptahydrate in 100 cc. water. The tempenature was to C.At the end of the reaction the mixture is acidified at low temperatureuntil the iron salt precipitate is completely dissolved. The solution isextracted with ether and the ether extract is treated with a bicarbonatesolution. By acidifying the latter, epsilon-azido-valerianic acid, notknown until now, is obtained.

EXAMPLE 20 30 g. cyclohexanone peroxide are added, while stirring, to asolution containing 40 g. ferrous sulfate in 100 00. water. A slightstream of sulfur dioxide is also introduced, the SO -excess is thenremoved, barium hydroxide is added until alkalinity, the bariumhydroxide excess is precipitated with CO and is filtered. Byconcentrating the filtrate, the barium salt of epsilon-sulfonate-caproicacid, not known until now, is separated. The alkaline salts of said acidare good detersives, i.e. detergents.

Analysis.-Found: C, 21.90%; H, 3.12%; S, 9.72%; Ba, 41.65%. Calculatedfor C H O SBa: C, 21.68%; H, 3.02%; S, 9.68%; Ba, 41.44%.

The same result is attained by employing Cu O instead of F3804.

EXAMPLE 21 13 g. cyclopentanone peroxide are added while agitating to 5g. CuSO -5H O, 24 g. sodium thiosulfate pentahydrate in 100 cc. water.Temperature 5 to 0 C.

At the end of the reaction the neutral portion is separated and stronglyacidified with hydrochloric acid; the solution is heated to boiling andthen, by cooling, epsilonepsilon'-dithio-di-valeric acid is separated.

EXAMPLE 22 12 g. 1-oxy-1'-hydroperoxy-cyclohexyl-peroxide are addedwhile stirring to 5 g. CuSO -5H 0, 24.8 g. Na- S O -5H 0 in 100 cc.water. The temperature was 15 to 20 C. At the end of the reaction theneutral portion, mainly consisting of cyclohexanone, is separated andthe solution is strongly acidified with hydrochloric acid. The solutionis then heated to boiling and, after a few minutes, an oil begins toseparate which solidifies by cooling. Theepsilon-cpsilon-dithiodicaproic acid,

H000 (CH -SS(CH COOH,

crystallized from water, melts at 82 C.

Acidimetric equivalent: Found 148.11 Calculated for C H 0 S 147.21

The products are obtained accord-ing to the present invention can ingeneral be employed as intermediates for obtaining commercial productsof a wide use, as it is shown in the following illustrative examples.

EXAMPLE 23 To a solution containing 6 g. cuprous cyanide and 9 g.potassium cyanide in 40 cc. water, 20 g. cyclopentanone peroxide areadded while agitating. The temperature is kept at 10 to 15 C.

When the reaction is completed, sodium hydroxide is added and themixture is refluxed'for 1 hour. After filtration and acidification 6 g.adipic acid are obtained.

EXAMPLE 24 30 g. methylethylketone perioxide are added under nitrogenwhile stirring to a solution of 10 g. cuprous sulfocyanide and 15 g.ammonium sulfocyanide in 60 cc. water. Temperature is kept at 0 to 5 C.during the addition which is completed within 40 minutes. The unreactedcuprous sulfocyanide (9 g.) is filtered ofi, the solution is acidifiedand extracted repeatedly with chloroform. The chloroform extract istreated with a sodium carbonate solution and then evaporated; theresidue is subjected to fractionation thus obtaining 2 fractions, thefirst one consisting of methylethylketone, the second one ofethylsulfocyanide: M.P. 142-143 C.

From the alkaline solution of the latter, acetic acid is recovered byacidification.

EXAMPLE 25 The reaction is carried out as in Example 10 but when it iscompleted, the undissolved copper salt is filtered ofi, the solution isacidified and boiled for 30 minutes. Pimelic acid (6 g.) is crystallizedby cooling.

My copendin-g application Serial No. 734,448 discloses processes forpreparing an epsilon-halo-caproic acid, in which the halo substituent istaken from the group consisting of chlorine, bromine, and iodine,comprising treating cyclohexanone peroxide with a member of the groupconsisting of hydrohah'c acids, alkali metal halides, and alkaline earthmetal halides in the presence of a redox promoter comprising a heavymetal salt in which the metal is a multivalent metal and is present in alower valence state, at a temperature of about -20 to +50 C., andcontains the following 14 examples:

Example 1 33 g. l-oxy-1'-hydroperoxy-cyclohexylperoxide are added to cc.water, 25 g. cuprous chloride and 60 g. 36% hydrochloric acid undernitrogen while stirring. The temperature is kept at between 0 and 5 C.The oily layer is decanted and, by treatment with Na CO 12 gramscyclohexanone and 20 grams epsilon-chloro-caproic acid (melting point 25C.) are separated.

Example 2 25 g. cyclohexanone are treated overnight with 9 g. hydrogenperoxide in ether at room temperature. The resulting solution is addedto 60 cc. water, 40 g. concentrated hydrochloric acid and 20 g. cuprouschloride at a temperature of between 5 C. and 0 C. under nitrogen, whilestirring.

The ether layer is separated and, after treatment with Na CO 27 g.epsilon-chloro-caproic acid and 6 g. cyclohexanone are obtained.

Example 3' 33 g. 1-oxy-1'-hydroperoxy-cyclohexylperoxide are added to100 cc. water, 25 g. cuprous chloride and 30 g. sodium chloride, whilestirring at a temperature between 0 and 5 C. When the reaction iscompleted, the mixture is acidified with sulfuric acid. The oily layeris decanted, fromwhich 18 g. epsilon-chloro-caproic acid and 11 g.cyclohexanone are obtained, by treatment with sodium or potassiumhydroxide.

Example 4 12 g. cuprous oxide are suspended in 100 cc. water in which 18g. sodium chloride have been dissolved. 20 g. 1-oxy-1-hydroperoxy-cyclohexylperoxide are then added under nitrogen whilestirring. The temperature slowly rises up to 38 C. When the reaction iscompleted the reaction mixture is acidified, with sulfuric acid forexample, and the oily layer is decanted. By treatment with alkali 6.5 g.cyclohexanone and 8.5 g. of an acidic product are obtained. The latterby distillation gives 4 g. caproic acid and 4.2 g.epsilon-chloro-caproic acid.

Example 5' To a solution of 63 g. FeSO .7H O and 30 g. NaCl in 200 cc.water, are added 30 g. 1-oxy-1-hydroperoxycyclohexylperoxide undernitrogen while stirring, at a temperature of 5-10 C. The reactionmixture is acidified when the reaction is completed and the oily layerformed is decanted. By treatment with Na CO 9.5 g. cyclohexanone and 19g. epsilon-chloro-caproic acid are separated.

Example 6' 14 g. iron powder are treated under nitrogen with 100 cc. 36%hydrochloric acid. To the solution thus obtained 30 g.l-oxy-l-hydroperoxy-cyclohexylperoxide are added at a temperaturebetween 35 and 45 C. while stirring. After decantation of the oily layerand treatment with NaOH, 12 g. cyclohexanone and 11 g.epsilonchloro-caproic acid are separated.

Example 7' To a mixture of 25 g. cuprous chloride, 150 cc. methylalcohol and 60 g. 36% hydrochloric acid, 33 g. 1-oxy-l'-hydroperoxy-cyclohexylperoxide dissolved in 300 cc. methanol are addedunder nitrogen while stirring. The temperature gradually rises to 45 C.Alcohol, water and cyclohexanone are distilled off and the residue isdissolved in water and extracted with ether. By evaporating ether, 8 g.epsilon-chloro-caproic acid are obtained.

Example 8' 33 g. 1-oxy-l-hydroperoxy-cyclohexylperoxide are added to 18g. cuprous chloride, 80 g. 40% hydrobromic acid and 100 cc. water undernitrogen while stirring, at a temperature of -5 C. The oily layer isdecanted and, by treatment with CaCl 11.5 g. cyclohexanone and 23.4 g.epsilon-bromo-caproic acid (melting point 36 C.) are obtained.

Example 9' 25 g. cyclohexanone are treated at room temperature overnightwith 9 g. hydrogen peroxide in ether; the resulting solution is added to60 cc. water, 20 g. hydrobromic acid and 18 g. cuprous chloride at atemperature between and 0 C. under nitrogen while stirring. By operatingas in the preceding example, 34 g. epsilonbromocaproic acid and 7.5 g.cyclohexanone are obtained.

Example 10' To a mixture of 250 cc. water, 40 g. potassium bromide and20 g. cuprous chloride, 30 g. 1-oxy-1'-hydroperoxy-cyclohexylperoxideare added under nitrogen while stirring. Temperature is kept at between25 and 30 C. After acidification when the reaction is completed, theoily layer formed is decanted and, operating as in the precedingexample, 20 g. epsilon-bromo-caproic acid and 12 g. cyclohexanone areobtained.

Example 11' 20 g. l-oxy-l'-hydroperoxy-cyclohexylperoxide are addedunder nitrogen to a solution of 63 g. FeSO .7H O and 20 g. hydrobromicacid in 200 cc. water while stirring. The temperature rises up to 45 C.during the addition. The oily layer is decanted and, as in the precedingexample, 14.5 g. cyclohexanone and 11.3 g. epsilonbromo-caproic acid areseparated.

Example 12 25 g. l-oxy-l-hydroperoxy-cyclohexylperoxide are added to amixture of 15 g. cuprous chloride, 25 g. hydroiodic acid in cc. waterunder nitrogen while stirring, at a temperature in the range of 0-5 C.The separated oil is decanted and, by adding sodium bicarbonate, theacidic portion (14 g.) is separated from cyclohexanone (12 g.). The acidmelts at 38-40 C. After crystallization from petroleum ether it melts at42 C.

Example 13' 24 g. epsilon-bromo-caproic acid and 260 cc. 25% ammonia arekept at room temperature for 6 days in a corked flask. Water and theammonia excess are distilled off and the solid residue is taken againwith boiling ethyl alcohol which dissolves ammonium bromide. The residuehas a melting point of -175" C. After crystallization from a mixturemethanol/ether 10 g. epsilonamino-caproic acid are obtained. Ammoniumbromide is recovered by evaporation of alcohol.

Example 14' 20 g. epsilon-chloro-caproic acid are neutralized with 10%NaOH and refluxed with 8.9 g. potassium cyanide for 5 hours. Aftercooling and acidification it is repeatedly extracted with ether. Byevaporation of ether 14.3 g. epsilon-cyano-caproic acid are obtained.

The dior poly-carboxylic acids described above also have utility in thepreparation of condensation polymers, by reaction with the usual diorpoly-arnines, amino acids, and dior poly-hydroxy compounds. The alkalinesalts of the various mono-carboxylic and poly-carboxylic acids describedhave utility as detergents, wetting agents, etc. The epsilon-cyanogroups can be converted by the usual catalytic hydrogenation, to aminogroups.

The new process is generally defined as designed to obtainepsilon-substituted derivatives of caproic acid from peroxides, and ischaracterized in that an oxy-peroxide having the following generalformula \OORI wherein R and R are equal or ditferent groups, consistingof H or an alkyl or cycloalkyl, is reacted with a hydrohalic acid or analkaline halide, cyanide, sulfocyanide, thiosulfate or azide or sulfurdioxide, thus obtaining halogen-, cyano-, sulfocyano-, dithiooraxidoderivatives or sulfonic acids, respectively, and in that thereaction is carried out at between 20 and +50 C., preferably in aqueoussolution at between 10 and +10 C., in the presence of substances capableof causing the decomposition of the peroxide into free radicals, inparticular the salts of heavy metals having a variable valence, in theirlower valence.

I claim:

1. A process of making an omega-azide of an aliphatic carboxylic acid,comprising treating a peroxide of a cycloaliphatic ketone having thelinkage HO\ /OOH the cycloaliphatic ring S of which is a saturatedhydrocarbon ring of five to six ring carbon atoms, said ring having assubstituents members of the group consisting of hydrogen and loweralkyl; the treating being with an azide of the class consisting of thealkali group and alkaline earth group azides, in the presence of a redoxreducing agent taken from the group consisting of cuprous oxide, andcuprous and ferrous salts at about -20 to +50 C.

2. A process of making an omega-sulfocyanide of an aliphatic carboxylicacid, comprising treating a peroxide of a cycloaliphatic ketone havingthe linkage HO\ OOH the cycloaliphatic ring S of which is a saturatedhydrocarbon ring of five to six carbon atoms, said ring having assubstituents members of the group consisting of hydrogen and lower alkylwith a sulfocyanide of the class consisting of the alkali group andalkaline earth group sulfocyanides, in the presence of a redox reducingagent of the group consisting of cuprous oxide, and cuprous and ferroussalts at about 20 to +50 C.

3. The process of claim 2, the sulfocyanide being ammonium sulfocyanide,the redox agent being cuprous sulfocyanide.

4. The process of claim 2, the sulfocyanide being ammonium sulfocyanide,the redox agent being ferrous sulfate.

5. A process of making an omega-dithio-di-carboxylic acid, comprisingtreating a peroxide of a cycloaliphatic ketone having the linkage HO OOHthe cycloaliphatic ring S of which is a saturated hydrocarbon ring offive to six ring carbon atoms, said ring having as substituents membersof the group consisting of hydrogen and lower alkyl; the treating beingwith a thiosulfate taken from the class consisting of the alkali groupand alkaline earth group thiosulfates, in the presence of a redoxreducing agent taken from the group consisting of cuprous oxide, andcuprous and ferrous salts.

6. A process of making an omega-sulfonate of an aliphatic carboxylicacid, comprising reacting a peroxide of a cycloaliphatic ketone havingthe linkage the cycloaliphatic ring S of which is a saturatedhydrocarbon ring of five to six ring carbon atoms, said ring having assubstituents members of the group consisting of hydrogen and loweralkyl; with sulfur dioxide in the presence of ferrous sulfate.

7. The compound epsilon-azido-caproic acid.

8. The compound epsilon-azido-valerianic acid.

9. The compound epsilon-sulfonate-caproic acid.

10. The process of claim 5, the ketone peroxide being cyclopentanoneperoxide, the thiosulfate being sodium thiosulfate, the redox agentbeing cuprous sulfate.

11. The process of claim 5, the ketone peroxide being cyclohexanoneperoxide, the thiosulfate being sodium thiosulfate, the redox agentbeing cuprous sulfate.

12. The process of claim 1, the ketone being cyclohexanone, the azidebeing sodium azide.

13. The process of claim 1, the ketone being cyclopentanone, the azidebeing sodium azide.

14. The process of claim 2, the sulfocyanide being ammoniumsulfocyanide.

15. A process of making epsilon-cyanocaproic acid comprising treatingl-oxy 1 hydroperoxy cyclohexylperoxide with cuprous cyanide andpotassium cyanide in aqueous medium at -20 to C.

16. A process of making adipic acid, comprising treating cyclopentanoneperoxide with cuprous cyanide and potassium cyanide in water at -20 to+50 C. and refluxing the product in aqueous alkali.

References Cited in the file of this patent UNITED STATES PATENTS2,376,105 Williams May 15, 1945 2,710,302. Hyson June 7, 1955 2,811,551Cotfman et a1. Oct. 29, 1957 2,839,576 Phillips June 17, 1958 2,870,201Pollack Ian. 20, 1959 2,880,220 Johnston Mar. 31, 1959 OTHER REFERENCESNischk: Ann. der Chemie, Vol. 576, pages 232-4 (1952).

Hill: J. Org. Chem. (London), Vol. 19, pages 1802-6 (1954).

Leonard: J. Am. Chem. Soc., Vol. 76, pages 5708-14 (1954).

1. A PROCESS OF MAKING AN OMEGA-AZIDE OF AN ALIPHATIC CARBOXYLIC ACID,COMPRISING TREATING A PEROXIDE OF A CYCLOALIPHATIC KETONE HAVING THELINKAGE